// Copyright (c) 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef NET_ANDROID_KEYSTORE_H
#define NET_ANDROID_KEYSTORE_H

#include <jni.h>
#include <stdint.h>

#include <string>
#include <vector>

#include "base/android/scoped_java_ref.h"
#include "base/strings/string_piece.h"
#include "net/base/net_export.h"
#include "net/ssl/ssl_client_cert_type.h"

// Misc functions to access the Android platform KeyStore.

namespace net {
namespace android {

    struct AndroidEVP_PKEY;

    // Define a list of constants describing private key types. The
    // values are shared with Java through org.chromium.net.PrivateKeyType.
    // Example: PRIVATE_KEY_TYPE_RSA.
    //
    // This enum is used as part of an RPC interface, so new values must be
    // appended and not reused.
    //
    // A Java counterpart will be generated for this enum.
    // GENERATED_JAVA_ENUM_PACKAGE: org.chromium.net
    enum PrivateKeyType {
        PRIVATE_KEY_TYPE_RSA = 0,
        // Obsolete: PRIVATE_KEY_TYPE_DSA = 1,
        PRIVATE_KEY_TYPE_ECDSA = 2,
        PRIVATE_KEY_TYPE_INVALID = 255,
    };

    // Returns the modulus of a given RSAPrivateKey platform object,
    // as a series of bytes, in big-endian representation. This can be
    // used with BN_bin2bn() to convert to an OpenSSL BIGNUM.
    //
    // |private_key| is a JNI reference for the private key.
    // |modulus| will receive the modulus bytes on success.
    // Returns true on success, or false on failure (e.g. if the key
    // is not RSA).
    NET_EXPORT bool GetRSAKeyModulus(jobject private_key,
        std::vector<uint8_t>* modulus);

    // Returns the order parameter of a given ECPrivateKey platform object,
    // as a series of bytes, in big-endian representation. This can be used
    // with BN_bin2bn() to convert to an OpenSSL BIGNUM.
    // |private_key| is a JNI reference for the private key.
    // |order| will receive the result bytes on success.
    // Returns true on success, or false on failure (e.g. if the key is
    // not EC).
    bool GetECKeyOrder(jobject private_key, std::vector<uint8_t>* order);

    // Compute the signature of a given message, which is actually a hash,
    // using a private key. For more details, please read the comments for the
    // rawSignDigestWithPrivateKey method in AndroidKeyStore.java.
    //
    // |private_key| is a JNI reference for the private key.
    // |digest| is the input digest.
    // |signature| will receive the signature on success.
    // Returns true on success, false on failure.
    //
    NET_EXPORT bool RawSignDigestWithPrivateKey(jobject private_key,
        const base::StringPiece& digest,
        std::vector<uint8_t>* signature);

    // Return the PrivateKeyType of a given private key.
    // |private_key| is a JNI reference for the private key.
    // Returns a PrivateKeyType, while will be CLIENT_CERT_INVALID_TYPE
    // on error.
    NET_EXPORT PrivateKeyType GetPrivateKeyType(jobject private_key);

    // Returns a handle to the system AndroidEVP_PKEY object used to back a given
    // private_key object. This must *only* be used for RSA private keys on Android
    // < 4.2. Technically, this is only guaranteed to work if the system image
    // contains a vanilla implementation of the Java API frameworks based on Harmony
    // + OpenSSL.
    //
    // |private_key| is a JNI reference for the private key.
    // Returns an AndroidEVP_PKEY* handle, or NULL in case of error.
    //
    // Note: Despite its name and return type, this function doesn't know
    //       anything about OpenSSL, it just type-casts a system pointer that
    //       is passed as an int through JNI. As such, it never increments
    //       the returned key's reference count.
    AndroidEVP_PKEY* GetOpenSSLSystemHandleForPrivateKey(jobject private_key);

    // Returns a JNI reference to the OpenSSLEngine object which is used to back a
    // given private_key object. This must *only* be used for RSA private keys on
    // Android < 4.2. Technically, this is only guaranteed to work if the system
    // image contains a vanilla implementation of the Java API frameworks based on
    // Harmony + OpenSSL.
    base::android::ScopedJavaLocalRef<jobject> GetOpenSSLEngineForPrivateKey(
        jobject private_key);

    // Register JNI methods
    NET_EXPORT bool RegisterKeyStore(JNIEnv* env);

} // namespace android
} // namespace net

#endif // NET_ANDROID_KEYSTORE_H
